1. Talk one: Biological Perspective To get you thinking and talking
Human Biology (BIOL 104)
Talk one: Biological Perspective
To get you thinking and talking

2. Levels of Biological Organization
The biological levels of organization of living things.
From a single organelle to the entire biosphere, living organisms are parts of a highly structured hierarchy.
credit “organelles”: modification of work by Umberto Salvagnin;
credit “cells”: modification of work by Bruce Wetzel, Harry Schaefer/ National Cancer Institute;
credit “tissues”: modification of work by Kilbad; Fama Clamosa; Mikael Haggstrom;
credit “organs”: modification of work by Mariana Ruiz Villareal;
credit “organisms”: modification of work by "Crystal"/Flickr;
credit “ecosystems”: modification of work by US Fish and Wildlife Service Headquarters;
credit “biosphere”: modification of work by NASA)
Copyright: OpenStax Biology for AP Courses, OpenStax, and Rice University

3. The scientific method
First documented by England’s Sir Francis Bacon (1561–1626) who set up inductive methods for scientific inquiry.
Biologists study the living world by posing questions about it and seeking science-based responses.
This approach is common to other sciences as well and is often referred to as the scientific method.
Sir Francis Bacon (1561–1626) is credited with being the first to define the scientific method. (credit: Paul van Somer).
Copyright: OpenStax Biology for AP Courses, OpenStax, and Rice University

4. The scientific method
Typically starts with an observation (often a problem to be solved) that leads to a question.
A hypothesis is a suggested explanation that can be tested. To solve a problem, several hypotheses may be proposed.
A valid hypothesis must be testable. It should also be falsifiable, meaning that it can be disproven by experimental results.
Importantly, science does not claim to “prove” anything because scientific understandings are always subject to modification with further information.
Copyright: OpenStax Biology for AP Courses, OpenStax, and Rice University

5. Scientific theories
Animals, plants, and bacteria are examples of living systems that share many properties distinguishing them from nonliving things. These properties are branched into theories.
Cellular organization
Fundamental unit of life is the cell – all living things are made up of cells.
Metabolism
Living things take up energy-rich materials and give out waste to environment. Some energy fuels life processes some accumulates and is released after death.
Selective response
Living things respond selectively to stimulation in the environment. Organisms recognize certain chemicals as nutrients while ignoring others.

6. Scientific theories Homeostasis
Living systems have some capacity to change harmful conditions into conditions more favorable to their continuing existence – the conversion of chemical compounds.
Growth and biosynthesis
Living systems go through phases during which they make more of their own material.
Genetic material
Living systems contain genetic material (DNA and RNA) to allow inherited traits.
Reproduction
Living systems can reproduce & pass on genetic material.
Population structure
Organism form populations. Of these organism capable of sexual processes, a population is all those organisms that can interbreed with one another.

7. From the wikimedia free licensed media file repository
Ethical thinking
Ethics is a discipline dealing with the analysis of moral rule and the ways in which moral judgments are made and justified.
Would you park your car in this space?
Why?
From the wikimedia free licensed media file repository

8. What benefits could come from nuclear power?
Nuclear power plants emit less than 1/100th the greenhouse gases of coal or gas power stations
Nuclear energy has the lowest harmful impacts on the environment - do not emit harmful gases - does not burn anything to produce electricity
Nuclear energy is the most "ecologically efficient“ of all energy sources
Produce the most electricity in relation to its minimal environmental impact
The nuclear energy also does not produce carbon dioxide or other greenhouse gases which can cause global warming
Used with permission from Think Global Green

9. Chernobyl Nuclear Disaster
April 26, 1986 in the Ukraine,
It is regarded as the worst accident in the history of nuclear power.
A plume of radioactive fallout drifted over parts of the western Soviet Union, Eastern and Western Europe, Scandinavia, the British Isles, and eastern North America. Large areas of Ukraine, Belarus, and Russia were badly contaminated
Resulted in the evacuation and resettlement of over 336,000 people. About 60% of the radioactive fallout landed in Belarus, according to official post-Soviet data
From the wikimedia free licensed media file repository

10. Chernobyl Nuclear Disaster
Two hundred people were hospitalized immediately, of whom 31 died (28 of them died from acute radiation exposure).
Most of these were fire and rescue workers trying to bring the accident under control
At least 8,000 people have died, most from radiation-related diseases.
About 2,000 people have been diagnosed with thyroid cancer and between 8,000 and 10,000 cases are expected to develop over the next 10 years.
From the wikimedia free licensed media file repository

11. Chernobyl Nuclear Disaster
From the wikimedia free licensed media file repository

12. Chernobyl Nuclear Disaster
thepurebar.com 
forum.prisonplanet.com 

13. From the wikimedia free licensed media file repository
Rights
Do animals have rights?
Nearly all new drugs, cosmetics, food additives, new forms of surgery are tested on animals first
Many societies have historically denied even the most basic of rights to classes of persons on the basis of economics, gender, race, ethnicity, or religious beliefs
From the wikimedia free licensed media file repository

14. Experiments without consent
Humans as experimental subjects
Experiments on twins
Bone, muscle, and nerve transplantation experiments
Head injury experiments
Freezing experiments
Malaria experiments
High Altitude and pressure experiments
From the wikimedia free licensed media file repository

15. Experiments without consent
1932 The Tuskegee Syphilis Study begins.
200 African-American men infected with syphilis are never told of their illness, are denied treatment, and instead are used as human guinea pigs in order to follow the progression and symptoms of the disease.
95% all subsequently die from syphilis, their families never told that they could have been treated.
Voluntary informed consent
Both a moral and legal issue
As there are lawyers under every rock!
Charlie Pollard
Herman Shaw
From the wikimedia free licensed media file repository

16. From the wikimedia free licensed media file repository
Thalidomide
Gender bias
What happens if this is not considered
It was only in 1992 that women were included in medical trials of new drugs by law!
Thalidomide (Kevadon®)
Developed as a morning sickness drug in the 1950s
BUT – never tested on women
Led to a generation of deformities
From the wikimedia free licensed media file repository

17. So, how did Thalidomide affect DNA?
So, things to remember:
All genes are coded for at the genetic level by four nucleotide bases (A, C, G, and T) and each gene has a unique coding and relative ratio of these bases.
Gene expression is highly regulated:
Promoters, enhancers, and repressors
In limb development, the genes involved have a VERY HIGH relative ratio of guanine (G).

18. From the wikimedia free licensed media file repository
Thalidomide
The structure of thalidomide is similar to that of the DNA purine bases adenine (A) and guanine (G).
In solution, has almost no affinity for the other nucleotides, cytosine (C) and thymine (T).
Furthermore, thalidomide can intercalate into DNA, presumably at G-rich sites.
From the wikimedia free licensed media file repository

19. From the wikimedia free licensed media file repository
Thalidomide
Thalidomide or one of its metabolites intercalates into these G-rich promoter regions, inhibiting the production of proteins and blocking development of the limb buds.
This intercalation would significantly affect the genes that rely primarily on guanine (G) sequences.
Most other developing tissues in the embryo rely on pathways without guanine, and are therefore NOT affected by thalidomide
From the wikimedia free licensed media file repository

20. From the wikimedia free licensed media file repository
Thalidomide
In UK alone there were 12,000 victims.
Sometimes functional feet and hands were amputated to allow the fitting of lower- and upper-limb Prosthesis in order for the children to appear “normal”.
Special school were set up too, in an attempt to keep the children out of sight and out of the minds of the public.
From the wikimedia free licensed media file repository

21. From the wikimedia free licensed media file repository
Thalidomide
Victims of the 1970s Thalidomide scandal have passed their deformities on to their children.
Thalidomide altered the coded regions for limb development in the G-rich promoter regions of the victims to replication of these regions during the production of gametes during Meiosis
– so arms and legs are not developed!
From the wikimedia free licensed media file repository

22. From the wikimedia free licensed media file repository
Thalidomide, Still?!!!!!!
Still in use today
Cancer treatments
by cutting off the flow of blood to tumors
Leprosy
is an infectious disease caused by a DNA plasmid
invades human nerves.
If untreated can eventually cause a variety of skin problems, loss of feeling, and paralysis of the hands and feet .
From the wikimedia free licensed media file repository

23. Genetically modified crops
All plant characteristics, such as size, texture, and sweetness, are determined on the genetic level.
Also:
The hardiness of crop plants.
Their drought resistance.
Rate of growth under different soil conditions.
Dependence on fertilizers.
Resistance to various pests and diseases.
Used to do this by selective breeding 23

24. Genetically modified crops
Agrobacterium method
Uses the natural infection mechanism of a plant pathogen
Agrobacterium tumefaciens naturally infects the wound sites in dicotyledonous plant causing the formation of the crown gall tumors.
Capable to transfer a particular DNA segment (T-DNA) of the tumor-inducing (Ti) plasmid into the nucleus of infected cells where it is integrated fully into the host genome and transcribed, causing the crown gall disease.
So the pathogen inserts the new DNA with great success!!!

25. What people think of using GM Plants!
Survey carried out by:
The Scientist Magazine.
Feb 2004, No/15401
302 readers responded to survey
Yes, a small group, as there are seven billion people on the planet
Interesting questions!
What to YOU think?
The Scientist Magazine

26. Genetically modified crops
Issues:
Destroying ecosystems – tomatoes are now growing in the artic tundra with fish antifreeze in them!
Destroying ecosystems – will the toxin now being produced by pest-resistance stains kill “friendly” insects such as butterflies.
Altering nature – should we be swapping genes between species?

27. Genetically modified crops
Issues:
Vegetarians – what about those tomatoes?
Religious dietary laws – anything from a pig?
Cross-pollination – producing a super-weed
Human health – what of the antibiotic marker gene?

28. The End.
Any Questions? 28